And I'm Audie Cornish. Strong words today from the United States and from Russia on the standoff in Ukraine. Secretary of State John Kerry made an emphatic appearance in the Ukrainian capital. He pledged U.S. support for the fledgling government and he expressed surprise at today's comments from Russian President Vladimir Putin.

BLOCK: Putin told journalists in Moscow that Russian troops had not invaded the Crimean peninsula. He said the troops were, in fact, local self-defense forces. At the same time, Putin did not rule out the use of Russian military force. Here he is heard through an interpreter on CNN.

PRESIDENT VLADIMIR PUTIN: (Through interpreter) You can see the unlawfulness starting in the east and if the requests are fulfilled, we leave the right for ourselves to take all measures to protect the rights of these people and we consider it quite legitimate. This is a final measure.

BLOCK: A final measure. Others translated that as a last resort.

CORNISH: Well, Secretary Kerry wasn't buying that denial of a Russian troop presence in Crimea. He condemned what he called Russia's act of aggression.

SECRETARY JOHN KERRY: Russia, if it wanted to help deescalate this situation could return its troops to the barracks and deescalate rather than expand their invasion.

BLOCK: And as John Kerry spoke in Kiev, back in Washington, President Obama simultaneously addressed the issue. He said there's still a chance for Russia to work with the international community to stabilize the situation.

PRESIDENT BARACK OBAMA: We've sent a clear message that we are prepared to work with anybody if their genuine interest is making sure that Ukraine is able to govern itself.

CORNISH: The U.S. is considering sanctions if Moscow does not pull troops out of Crimea. NPR's Michele Kelemen is traveling with Secretary Kerry and joins us now. And Michele, first of all, Kerry offered economic support to Ukraine. What does that include?

MICHELE KELEMEN, BYLINE: That's right. He came here with an offer of a billion dollars in loan guarantees. It's meant to offset any losses for Ukraine when it cuts back on energy subsidies. That's one of the many reforms that Ukraine's going to need to do to get its fiscal house in order and to receive a bailout package from the International Monetary Fund. The U.S. is also offering technical assistance to help Ukraine deal with what could become a trade war with Russia.

And the U.S. has a program to help Ukrainians recover stolen assets, train election monitors ahead of a planned vote in May. So various programs really to help this new team in Kiev financially, but also politically.

CORNISH: And who was Secretary Kerry meeting with there? What was he doing?

KELEMEN: He spent a while at the Ukrainian parliament building meeting all the major figures from the protest movement so we met with the interim president, the prime minister and many others, but, you know, the most interesting part of the day, Audie, was his visit to this makeshift memorial to dozens of people that were killed by snipers on a day in late February, February 20.

The barricades are still there. There's the smell of burning tires. There was a big crowd there, flowers and candles and he talked about how moved he was really to be there.

CORNISH: Now, obviously a very different point of view has been outlined by Vladimir Putin. He describes Russians living in eastern Ukraine as being under threat. What did Secretary Kerry hear about that and how did he respond?

KELEMEN: Well, at the end of the day, at a news conference, he said that it's time to set the record straight. He said the Russians are out of excuses. He was very forceful. He said Russia has been working hard to create a pretext to invade further and he said that the Ukrainian authorities have actually been acting quite responsibility and with a lot of restraint.

On the streets, he heard from people on the streets that this is not happening. I spoke to a rabbi who met with him there and he says, you know, the Russians keep saying we're all - that the people in the opposition, we're fascists and this is not true. He says, this is a provocation coming from Russia. And U.S. officials say they've not really seen evidence of what the Russians are saying.

They say they hope to persuade Putin to talk to Ukrainian officials about this and to have more international observers actually check what's happening, both in Crimea, but also in eastern Ukraine where there's a lot of Russian speakers and ethnic Russians. So the organization for security and cooperation in Europe has a small team here in Ukraine. The U.S. wants to see that expanded greatly.